Thread Starter


Joined Jan 13, 2012
hi...i was about to explain the operation of D flip-flop but im confuse...is the D latches same as the positive edge triggered flip flop? ....if it is not...which one is the right D flip flop for me to explain the operation?


Joined Oct 2, 2009
The names flip-flops and latches are sometimes confused, even though I don't think there is an official definition of a latch... just semantics.

A D flip-flop is usually implemented using a positive edge triggered flip-flop, but doesn't have to be.

A latch is usually transparent (Q follows D) when the CLOCK input is HIGH.
The output Q is latched when the CLOCK goes LOW.
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Joined Nov 25, 2009
That is the one definition of latch. I have also seen the word latch referring to the 2 NAND (or NOR) circuit that has only two SR inputs, latching only on two functions, SET, or RESET.

However, a D latch would refer to MrChips' definition, I guess.